\begin{tikzpicture}
  \begin{scope}[x=0.7cm, y=0.7cm, step=0.7cm, thick]
    \board{4}{3};  
    \qb{(2,2)};
    \qw{(1,2)};
    \arrow{(2, 1)};
    \arrow{(2, 3)};
    \arrow{(3, 2)};
    \arrow{(4, 2)};
    \arrow{(4, 1)};
  \end{scope}
\end{tikzpicture}

%% 5 . X . . X
%% 4 W B X X X
%% 3 . X . X .
%% 2 X X X X .
%% 1 . . . . .
%%   A B C D E
%% P-class
